A mobile industry processor interface (MIPI) switch can be used in a mobile phone to connect a central processing unit (CPU) with two cameras via a T topology. There are multiple differential signal pairs between the CPU and the cameras. For each differential signal pair, wiring lengths of the differential signal pair need to be equal. Additionally, for different differential signal pairs, wiring lengths of the different differential signal pairs need to be equal. Therefore, in PCB design, it is difficult and time-consuming to determine wiring paths of the differential signal pairs on a PCB.